K. Dürrschmid, D. Toprak, W. Kneifel
Department of Food Science and Technology, University of Natural Resources and Applied Life Sciences Vienna

In Austria, about 80% of the milk consumed can be assigned to the segment of fresh pasteurized milk. Meanwhile, other forms of milk like extended-shelf-life (ESL) and ultra-heat-treated (UHT) milk are increasingly offered by several producers due to convenience reasons. These three product categories are primarily characterized by their heat treatment, which usually leads to different sensory properties.

The aim of this study was therefore to quantify the hedonic acceptance of the two market leading fresh milks, two ESL milks and UHT milks, respectively. It was to clarify, if the information about the milk product category influences the hedonic acceptance evaluation. The six products were judged in affective terms of appearance, smell, taste, mouthfeeling and the over-all-impression by 250 non-trained consumers (five different groups aged from 10-14, 15-18, 19-30, 31-59, 60 plus) using five non-structured line scales in a coded and in a non-coded way. In the non-coded way, the samples were characterized as “fresh milk”, “extended shelf life milk” and “sterilized UHT-milk”.

The results of the hedonic tests in the coded design did not indicate any difference between fresh and sterilized UHT milk, but a slight preference for ESL milk against fresh milk. In the non-coded design, the fresh milks were judged in a much more better way and the sterilized and the ESL milks lost much of their hedonic acceptance. Depending on their age, the investigated consumer groups considered the product information to a different extent. In fact, the information about the way the products are produced pronouncedly influences the affective evaluation. This can be seen as an interesting example for how sensitive and complex consumers’ hedonic evaluation process is composed.